CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (132,617,160)	$ (76,925,380)	$ (89,875,459)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation of fixed assets	181,412	141,601	77,906
Amortization of intangible assets	112,474	71,516	54,545
Provision for doubtful accounts	216,022	4,206	2,524,909
Share-based compensation	8,661,967	6,889,323	17,411,021
Amortization of deferred financing costs	269,859
Changes in operating assets and liabilities:
Accounts receivable	(6,951,041)	167,691	(3,975,893)
Inventory	(1,782,312)	(409,037)	(386,168)
Other current assets	(2,332,335)	(4,434,130)	709,907
Other assets	(324,855)
Accounts payable	18,646,241	(3,260,914)	4,232,340
Accrued expenses and other current liabilities	9,107,947	1,599,510	84,559
Net cash used in operating activities	(106,811,781)	(76,155,614)	(69,142,333)
CASH FLOWS FROM INVESTING ACTIVITIES
Payment for intellectual property license	(20,000,000)
Patent costs	(1,105,407)	(765,291)	(845,266)
Purchase of fixed assets	(217,040)	(61,817)	(396,154)
Payment of security deposit	(175,410)		(14,036)
Net cash used in investing activities	(21,497,857)	(827,108)	(1,255,456)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from sale of common stock, net of costs	89,907,797	68,572,635	134,863,475
Proceeds from term loan	75,000,000
Payment of deferred financing fees	(3,786,918)
Proceeds from exercise of options	1,666,208	212,615	989,060
Proceeds from exercise of warrants		3,798,999	1,373,000
Net cash provided by financing activities	162,787,087	72,584,249	137,225,535
Increase (decrease) in cash	34,477,449	(4,398,473)	66,827,746
Cash, beginning of period	127,135,628	131,534,101	64,706,355
Cash, end of period	161,613,077	$ 127,135,628	$ 131,534,101
Supplemental disclosure of cash flow information
Interest paid	$ 1,890,166